1. Field of the Invention
The present invention relates to a novel anthraquinone compound, and more particularly to a novel anti-tumour anthraquinone compound.
2. Description of the Prior Art
The netropsin and its derivatives having polypyrrol molecular skeleton are known as effective or potential anti-virus compounds. Netropsin and its derivatives are proved to be effective to increase the survival rate of the animals infected by virus (e.g. mice infected by influenza A or B, mice infected by neutropic vaccinia virus or pigs infected by flu virus). The anti-virus ability of netropsin and its derivatives perhaps arises from the interaction between the DNA of virus and the guanido acetamide group of netropsin and its derivatives. It is thought that the guanido acetamide group of netropsin and its derivatives weaken the interaction between DNA polymerase and the DNA molecules. However, although the anti-virus ability of netropsin and its derivatives is proved, netropsin and its derivatives are not potential compounds for curing cancer, due to the reasons that the effect of the medication is unclear, the synthesis of the compound is difficult, the solubility of the compound is poor, and no anti-cancer ability of the compound is reported.
On the other hand, anthraquinone and its derivatives are used for anti-cancer purposes. Since the molecules of anthraquinone and its derivatives can insert into the double helix structure of DNA to interfere the replication of DNA, so that the proliferation of cancer cell can be further inhibited. However, most anthraquinone and its derivatives are highly toxic and with poor chemical selectivity.
Therefore, it may be an improvement to design and prepare a molecule to own the above effects simultaneously by combining anthraquinone and guanidoacetamide or benzyl carbamidoacetamide to selectively inhibit the replication of certain DNA, so that the proliferation of cancer cells can be selectively inhibited.
Accordingly, the present invention discloses novel anthraquinone compounds which have excellent selectivity, anti-virus and anti-cancer activity.
An object of the present invention is to provide a novel compound having an anthraquinone and a guanidoacetamide or benzyl carbarmidoacetamide group.
Another object of the present invention is to provide an anti-cancer pharmaceutic composition contains a novel anti-cancer compound having an anthraquinone and a guanidoacetamide or benzyl idoacetamide group.
One aspect of the present invention relates to a novel compound of the following formula (I), 
wherein R1, R2 and R3 each independently is hydrogen, hydroxy, amino or C1-6 alkyl group; R4 is hydrogen, C1-18 alkyl carbonyl, C1-6 alkyl group substituted by at least a functional group, said functional group is selected from the group consisting of hydroxyl, amino, carbado, carbazoyl, fonnyl, carbamyl, carboxyl, carbonyl, or a group of the 
wherein X is fluoro, chloro, bromo, iodo, or a group of the following formula 
wherein n is 1, 2, or 3, R6 is hydrogen or aromatic alkyl, or a group of the following formula 
wherein l is 1, 2, or 3, m is 0 or 1, n and R6 are defined as the above; R5 is hydrogen, amino or a group of the following formula 
wherein R1, R2, R3 and R4 are defined as the above; and R and Rxe2x80x2 each independently is hydrogen, hydroxyl, amino, C1-6 alkyl group or a group of the following formula 
wherein R1, R2, R3 and R4 are defined as the above.
In the novel compound of the present invention, R1, R2 and R3 are preferably hydrogen or amino; R4 is preferably hydrogen or a group of the following formula; and 
R and Rxe2x80x2 each independently is hydrogen, amino or a group of the following formula 
wherein R1, R2, R3 and R4 are defined as the above.
In a preferred embodiment of the novel compound of the present invention, the R4 is a group of the following formula 
wherein n is 1, 2 or 3; R6 is hydrogen, 1-naphthyl, 2-naphthyl or a group of the following formula 
wherein p is 0, 1, 2, or 3; R7 and R8 each independently is hydrogen, hydroxyl, carbado, carbamyl, carboxyl, carbonyl, formyl, mercapto, methylthio, thioureido, thiocyanato, sulfoamoyl, sulfo, phosphono, fluoro, chloro, bromo, iodo, cyano, trifluoro methyl, C1-6 alkyl group, C1-6 alkoxy group, dimethyl amino, and benzyloxy, C1-18 alkoxycarbonyl, or arylmethoxycarbonyl, wherein said aryl group is phenyl, 2-methoxyphenyl, 4-methoxyphenyl, 2-fluorophenyl, 4-fluorophenyl, 2-chlorophenyl, 4-chlorophenyl, 2-bromophenyl, 4-bromophenyl, 1-naphthyl, 2-naphthyl, 9-fluorenyl, or pentafluorophenyl; and a pharmaceutically acceptable salt thereof.
It is further preferred that R4 is a group of the following formula 
wherein l is 1; m is 0; n is 1; R6 is a group of the following formula 
wherein p is 0 or 1; R7 and R8 each independently is hydrogen, hydroxyl, carbamyl, carboxyl, carbonyl, formyl, mercapto, methylthio, thioureido, thiocyanato, sulfoamoyl, sulfo, phosphono, fluoro, chloro, bromo, iodo, cyano, trifluoro methyl, C1-6 alkyl group, C1-6 alkyl oxide group, dimethyl amine, and benzyloxy, C1-18 alkoxycarbonyl, or aryl-methoxycarbonyl, wherein said aryl group is phenyl, 2-methoxyphenyl, 4-methoxyphenyl, 2-fluorophenyl, 4-fluorophenyl, 2-chlorophenyl, 4-chlorophenyl, 2-bromophenyl, 4-bromophenyl, 1-naphthyl, 2-naphthyl, 9-fluorenyl, or pentafluorophenyl; and a pharmaceutically acceptable salt thereof.
The present invention further provides a pharmaceutic composition which contains (1) an effective amount of formula (I) compound described above, and (2) one or more pharmaceutically acceptable carriers. An effective amount depends upon the condition being treated, the route of administration chosen, and the specific activity of the compound used, and ultimately will be decided by the attending physician or veterinarian.
The pharmaceutic composition of the present invention is an pharmaceutic composition with anti-virus ability. It can also effectively inhibit the proliferation of cancer cells. Preferably, the pharmaceutic composition of the present invention can be used for curing lung cancer, leukemia or brain cancer or AIDS.
The compounds of formula (I) of the present invention can be prepared by the following steps (as shown in scheme A or B), 
wherein R, Rxe2x80x2, R1, R2, R3, R4 and R5 are defined as the above. 
wherein R, Rxe2x80x2R1, R2, R3, R4 and R5 are defined as the above.
More detailed examples are used to illustrate the present invention, and these examples are used to explain the present invention. The examples below, which are given simply by way of illustration, must not be taken to limit the scope of the invention.